What's this?

This is just a repository of inspiration to help you insult people politely. Sometimes a "fuck you" is inevitable, desirable or just inescapable. But oftentimes a witty comeback can cut deeper and give you extra points for sounding smart.

Will I sound stupid if I use these in real life?

Yes.

Where did you get all the content?

From the internet. Places like Reddit, 9gag and others have plenty of ideas. I just put them all together.